The prior art drilling apparatus use an excavation bit for conventional (near surface to far surface) drilling, or a reverse reaming bit for far surface to near surface drilling, comprising one or more ground engaging formations mounted on the excavation bit. The round engaging formations can be either drag, button, tooth, disc, point attack or other cutters on the bit to excavate rock. The main disadvantages with these types of bits is that to produce a larger hole will require more cutters, and as such a greater torque and thrust must be applied to the bit. Thus an operator is limited in the size of bores that can be excavated by the amount of power available from the driving equipment. The operation of conventional bits is performed by the revolving of the body of the bit, which then causes the cutters and carrier to rotate because the cutters are in contact with the earth surface. This action then allows the cutters on the bit to excavate the earth beneath the bit. The crushing and/or cutting thrust onto the surface being excavated must be totally supplied to the drill bit from a rotational unit which also produces thrust. Additional thrust is supplied by the weight of the bit which is an advantage in some excavations and a disadvantage in others.